Mobile communication terminals, such as a cellular phone, have been experiencing improvement into the ever-higher performance of additional functions involving image display, such as a camera function and a TV broadcast receiving function. This advancement is accompanied by emergence of diversified structures of the display device. Although many conventional mobile communication terminals are equipped with a vertically long screen, a screen of horizontally long shape is suitable for use as a TV screen. Therefore, common mobile communication terminal come to provide a display device that can display images on a screen turned into a position where the screen is horizontally long.
In such mobile communication terminals, a display direction of an image is changed by detecting the horizontally long state of the casing itself. Besides, among mobile communication terminals having a foldable casing, one in which, by configuring that only a part corresponding to a display device can be rotated, only the display device can be directed in a vertically long direction or a horizontally long direction depending on the intended use is also used in practice. Thus, display control, depending on a plurality of screen directions, is performed.
Regarding a display device used for such a mobile communication terminal, one using a liquid crystal display panel is mainstream, and a stereoscopic image display technique using a liquid crystal display technique has also been established (for example, Japanese Patent No. 2857429).
Also, in such a stereoscopic image display technique, there is also a technique that can easily provide a three-dimensional image display without discomfort on the basis of a two-dimensional image (for example, Unexamined Japanese Patent Application KOKAI Publication No. 2004-320189).
By using the techniques as described above, a stereoscopic image display can be easily provided even in a small electronic device such as a mobile communication terminal. However, a stereoscopic image has the disadvantage of being difficult to visually recognize displays unless the display control that meets conditions upon viewing (e.g., visual distance and angle, distance between viewer's eyes, and the like) is performed. As described above, in any mobile communication terminal, a variety of configurations are available for a display device. Therefore, a user is unable to appropriately visually recognize a stereoscopic image when a posture of the device is changed, problematically.